Comment on Justin Henderson's review:

Long Stems for big rims.

Familiarity:
I've used it once or twice and have initial impressions

Lots of the current super-wide rims (think Enve M60, Ibis 941, and Industry Nine Torch) are also pretty deep. Most people riding them are running sealant rather than tubes, but these are the ticket for spares since they have 45mm valve stems. Tubes with shorter 35mm valve stems don't leave enough valve to get a pump or co2 inflator on.

Comment on Pete OBrien's review:

Fine tubes

Familiarity:
I've put it through the wringer

I've been riding Park City trails a lot lately, and just barely swapped over my wheels to a tubeless setup, so I've been relying on good tire/tube setups for the past three months. The trails here are pretty rocky, and I do every so often get snakebite flats from hitting jagged boogers straight on. These tubes have been a life saver on a few occasions when I'm 15-miles out from home. I've flatted two (2) tubes that came with the bike, and one (1) of these after barreling down a rock garden at ~25 mph.

Nothing fancy about them, but they work as good as the others. I'm not a tube geek, so don't ask me about weight.